New Australian study uses multi-trajectory modelling to examine early childhood weight

A new Australian study, conducted by Deakin University, has revealed that changes in lifestyle patterns are linked with changes in body mass index (BMI) in early childhood. 

The study found that maternal pre-pregnancy BMI, maternal dietary patterns and television viewing time are significant determinants in children’s BMI in early childhood, and is significant because it is the first study to use multi-trajectory modeling to examine the longitudinal relationship between concurrent changes in lifestyle patterns and BMI scores in early childhood.

“The findings will inform early childhood obesity prevention intervention and policy, and will be of great interest to pediatricians, researchers, policymakers and the general public,”  corresponding study author Miaobing Zheng said. 

Studies investigating the association between lifestyle patterns and obesity in children are scarce, researchers explained.In the present study, the co-occurrence of stable healthy lifestyle patterns along with a concurrent normal BMI z score trajectory of one unit from 18 to 60 months in about half of the children provides new longitudinal evidence supporting that children with healthy lifestyles were more likely to concurrently have normal BMI z score development.

To reach their findings, researchers used data collected from 439 children who were part of the Melbourne Feeding Activity and Nutrition Trial (InFANT) program. This longitudinal cohort of children commenced in 2008 as a 15-month parent-focused cluster randomized controlled trial aiming to reduce obesity risk behaviors in children until 18 months. 

Additional follow-ups without interventions occurred for children aged 42 and 60 months. Multi-trajectory modeling identified groups of children following similar lifestyle patterns and BMI z score trajectories and multinomial logistic regression assessed the determinants of the trajectory groups.

The children were classified into three distinct groups – those who had an unhealthy lifestyle pattern but low BMI (group one), those who had an unhealthy lifestyle with a high BMI (group three), and those who had a healthy lifestyle with mid range BMI (group two). 

When compared with groups one and three, children in group two had the most distinctive trajectories across lifestyle patterns and BMI z scores. 

Group two comprised nearly 53 percent of children and followed a stable and low trajectory for an unhealthy lifestyle pattern characterized by energy-dense and nutrient poor discretionary food consumption and television viewing time and a high and rising trajectory for a healthy lifestyle pattern of fruit and vegetable intakes and time outdoors, along with a mean BMI z score of +1 unit over time.

Groups one and three shared similar high trajectories for an unhealthy lifestyle pattern of discretionary food consumption and television viewing time, and low trajectories for a healthy lifestyle pattern of fruit and vegetable intakes and time outdoors. 

The two groups however differed in BMI z score trajectories, showing stable patterns but at mean scores of 0 and +2 units, respectively. Child sex, breastfeeding duration and maternal physical activity were not associated with the identified trajectory groups.

As a result of their findings, the authors noted that the co-occurrence of stable lifestyle patterns and BMI score trajectories pointed to the importance of initiating lifestyle obesity prevention early in life, and such interventions could target both children and the mother. A multi-behavior approach to simultaneously target healthy diet, physical activity and sedentary behaviors could be adapted.

The findings are available to review here.